textproduct: Quad Cities

KEY MESSAGES

- An Excessive Heat Warning remains in effect for the I-80 corridor on south through Friday with heat indices ranging from 100-105 degrees. A Heat Advisory remains in effect through Thursday north of I-80.

- The Storm Prediction Center has a Marginal, level 1 out of 5, Risk for severe storms for Thursday and Friday. The primary risk is damaging winds with hail a secondary risk.

- There is a near daily risk of showers and storms through Saturday, especially along and north of I-80. While there is a risk of rain, there will be plenty of dry hours.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 225 PM CDT Wed Sep 2 2026

The latest sfc analysis was indicating the main boundary(a west-to- east oriented quasi-stationary front) located just to the north along the IA/MN border into southern WI. Elevated convection continues to fester along and south of this feature from central into northeastern IA, and will have to maintain at least some low CHC POPs along Hwy 20 through early evening in case some of this activity drifts this way instead of passing to the north or falling apart like most CAMs show. Isolated pop-up storms possible to the southeast this evening acrs central IL. Otherwise with the placement of the upper ridge axis, expect a mainly dry overnight into Thursday morning with the more significant storm clusters occurring just to the northwest and north. However, with a another bout of backing and increasing LLJ action, there could be isolated to sctrd elevated showers and possibly a thunderstorm late tonight into Thu morning. Low temps tonight generally in the low to mid 70s again.

Thursday to be another hot ridging day with low to mid 90 ambient temps and sfc DPTS in the low to mid 70s supporting the ongoing heat headlines which will not be adjusted for now. There may be a chance for an isolated storm developing in the heating of the day, but the more organized ridge periphery storm track and short wave path still lies just to the north and expect an active convective Thursday night from the eastern Dakotas and acrs southern MN. Back to Thu afternoon and early evening, a weakening cap with mid level cooling over some lower level moisture convergence looks more favorable for pop-up storms acrs central into southeastern IL as opposed to our local area. While severe storms take off acrs southern MN, much of our local area may be dry again into early Friday morning. But then there are a few model solutions that bleed some of the late night storm clusters or MCS acrs northeast IA and southwest WI down into at least the northeastern DVN CWA by Friday morning, obviously using cold pool mechanics to dig this far south into the lingering ridge. This potential is driving the SPC day 2 outlook, but could also see the scenario where the convection never makes it down here by Friday, opening up the need to expand the heat headlines back north again for Friday afternoon.

Friday night there is definitely some uncertainty with the potential for outflow boundaries or the synoptic front itself to be adjusted further south and be a focus for evening or overnight storm development. The NBM loaded 20 to 50% POPs for Friday night for this scenario, but also could see it being another night of convective promise that turns into not much happening at all and storms deflected to the northeast.

LONG TERM /SATURDAY THROUGH TUESDAY/

Issued at 225 PM CDT Wed Sep 2 2026

Saturday through Monday...With the latest medium range run of ensembles continuing to show the brunt of the upper ridge axis shunted back to the west acrs the MO RVR Valley and eastern plains, Saturday may be a more optimum day of having a boundary or two(such as a northeast flow LK MI enhanced front) for storms to pop up on in the heating of the day. There also will be the potentail for another day of 100+ degree heat indices especially acrs the south half of the CWA and the need for heat headlines, especially taking into account the accumulative days of heat into account. Then hopefully the local area will become more under the influence of western GRT LKS sfc ridging for cooler, a bit less humid and mainly storm-free days for the second half of the holiday weekend.

Mid next week...still signs of the thermal ridge temporally getting shunted back up toward the region for an above normal temp surge Tue into early Wed, before a bigger cool front push and pattern change commences by Wednesday.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1239 PM CDT Wed Sep 2 2026

With the main sfc front wavering quasi-stationary style from west-to-east just to the north of the local area, will go with simple 1 line TAFs for now as just expecting south to southwesterly sfc winds of 4-8 KTs and VFR level clouds, if there are much of any clouds at all. But this goes with the caveat that there could be isolated to sctrd high based showers or even a thunderstorm after midnight into mid Thursday morning, but confidence and coverage not there enough to include this low potential in the TAFs at this time.

CLIMATE

Issued at 225 PM CDT Sun Aug 30 2026

Record Warm Low Temperatures:

September 3: KDBQ: 73/1939 KMLI: 76/1939

September 4: KDBQ: 71/1912 KMLI: 74/2018

September 5: KDBQ: 76/1881 KMLI: 76/1925

DVN WATCHES/WARNINGS/ADVISORIES

IA...Heat Advisory until 7 PM CDT Thursday for IAZ040>042-051>054- 066. Extreme Heat Warning until 7 PM CDT Friday for IAZ063>065-067- 068-076>078-087>089-098-099. IL...Heat Advisory until 7 PM CDT Thursday for ILZ001-002-007-009. Extreme Heat Warning until 7 PM CDT Friday for ILZ015>018- 024>026-034-035. MO...Extreme Heat Warning until 7 PM CDT Friday for MOZ009-010.